REAF;:IRM(O~OO ~ ",. .. -AI IS 9451 : 1994 ~m ~ if ~ ~ arrnr~ efi if11Tm f~T;a (~~T Tf~T~) Indian Standard GUIDELINES FOR LINING OF CANALS IN EXPANSIVE SOILS ( Second Revision ) 'It " © DIS 1994 BUREAU OF INDIAN STANDARDS MANAK BHAVAN, 9 BAHADUR SHAH NEW DELHI 110002 ZAFAR MARO February 1,994 Prle. Groa, 3 AM-ENDMENT NO.1 SEPTEMBER 2000 TO IS 9451: 1994 GUIDELINES FOR LINING OF CANALS IN EXPANSIVE SOILS (Second Revision) (Page 2, clause 5.2, Table lA ) - substitute 'swelling pressure' for 'swell pressure'. ( Page 3, clause 6.5, line 7) (LDPE)' for -WPH' . Substitute 'Low density polyethylene (Page 3, clause 6.s, line 11 ) - Substitute 'High molecular mass high density polyethylene (HDPB-HM)' for-·HDPB-HM·. (Page 4, Fig. 2) Substitute 'Cast-in-situ' for 'CIS'. (Page 4, Annex A ) - Insert C( second revision )' at the end of the title of IS 3873 : 1993. (Page 5, Anna A ) Insert C( fIrSt revision)' at the end of the title of IS 4515 : 1993. ( Page 5, Annex A ) following: 'Lining for canals by stone masonry Code of practice'. ' Substitute the title of IS 11809 : 1993 by the (WRDt3) ~ , Unit, BlS, New Delhi, India AMENDMENT NO. 2 NOVEBMER 2011 TO IS 9451 : 1994 GUIDELINES FOR LINING OF CANALS IN EXPANSIVE SOILS ( Second Revision ) (Page 1, clause 4.1, para 1, second sentence) ­­ Substitute `This characteristic of swelling and the swelling pressures of expansive soils is attributed to the presence of montmorillonite or combination of montmorillonite and illite clay minerals in such soils.' for `This characteristic of swelling and the swelling pressures of black cotton soils is attributed to the pressure of montmorinolite or combination of montmorinolite and illite clay minerals.' (Page 1, clause 4.1, para 2, first sentence) ­­ Substitute `The free swell index and swelling pressure tests should be done in accordance with IS 2720 (Part 40) and IS 2720 (Part 41) respectively.' for `The swelling pressure and free swell index tests should be done in accordance with IS 2720 (Part 40) : 1977 and IS 2720 (Part 41) : 1977.' (Page 1, clause 4.2.1, line 1) ­­ Substitute `Cohesive non-swelling soil' for `They'. (Page 2, clause 5.2, line 4) ­­ Substitute `IS 10430' for `IS 10430 : 1982'. (Page 2, Table 1A, Title) ­­ Substitute `Table 1A Thickness of CNS Layer for Canal Carrying Capacity of Less Than 2 Cumecs' for the existing. (Page 2, Table 1B, Title) ­­ Substitute `Table 1B Thickness of CNS Layer for Canal Carrying Capacity of 2 Cumecs and More' for the existing. (Page 2, Table 1B) ­­ Substitute `Thickness of CNS Layer in cm (Min)' for `Thickness of CNS Materials, cm (Min)'. [Page 4, clause 7.1] ­­ Substitute `IS 3872, for `IS 3872 : 1966', `IS 4515' for `IS 4515 : 1993', and `IS 11809' for `IS 11809 : 1993'. (Page 4, Annex A) ­­ Substitute `IS 2720 (Part 41) : 1977 Methods of test for soils : Part 41 Measurement of swelling pressure of soils' for the existing. (Page 4, Annex A) ­­ Substitute `IS 3872 : 2002' for `IS 3872 : 1966' and Amend No. 2 to IS 9451 : 1994 substitute the following for the existing title: `Lining of canals with burnt clay tiles -- Code of practice (first revision)'. (Page 5, Annex A) ­­ Substitute `IS 4515 : 2002' for `IS 4515 : 1993' and substitute the following for the existing title: `Stone pitched lining for canals -- Code of practice (second revision)'. (Page 5, Annex A) ­­ Substitute `IS 11809 : 1994' for `IS 11809 : 1993' and substitute the following for the existing title: `Lining of canals by stone masonry -- Code of practice (first revision)'. (Page 5, Annex A) ­­ Substitute `IS 10430 : 2000' for `IS 10430 : 1982' and substitute the following for the existing title: `IS 10430 : 2000 Criteria for design of lined canals and guidance for selection of type of lining (first revision)' (WRD 13) 1 2 Reprography Unit, BIS, New Delhi, India Irrigation Canals and Canal Lining. Sectional Committee, RVD 13 FOREWORD Thi. Indian Standard ( Second Revision) was adopted by the Bureau of Indian Standards, after the draft finalized by the Irrigation Canals and Canal Linings Sectional Committee had beeD approved by the River Valley Division Council. Canals excavated in elpansive soils, such as black cotten soil, pose several problems involving. stability of slopes and shape or section. To have economical sections and prevent erosion due to design velocities, it is necessary to line the canal bed and slopes. Precast cement concrete slabs for side slopes and in-situ concrete for bed are common types of lining adopted for canals in cutting and embankment. However, it is often experienced that the lining materials directly placed against the expansive soils undergo deformation by heaving, disturbing the lining and throwing the canal out of commission. This deformation is traced to the characteristics . swelling and swelling pressure developed by expansive soils, when they imbibe water in their intra-layers. Adequate thickness of cohesive non-swelling soil ( eNS) material is found to resist swelling pressure and prevent the heaving of underlying soil. From experiments in laboratory and field it is concluded that deformations may be correlated to the thickness of eNS layer and swelling pressure characteristics expansive soil. This standard Jays down guidelines for the treatment 0(expansive soil. by introduction of a cohesive non-swelling soil layer of suitable thickness between the expansive soil mass and the linin. material to counteract the swelling pressure and resultant deformation of the lining material on a scientific basil. or or This standard was first published in 1980 and the first revision was taken up in 1985. The second revision has been taken up in view of the experience gained during the course of these years in the use of this standard. The following major changes have been incorporated in this revision: 1) Identification and properties of expansive soil have been referred to the relevant Indian Standard. 2) Instead of three types of treatment only one type of treatment has been provided. 3) Modifications have been incorporated in Table 1. 4) Construction procedure for canal in cutting and embankment has been added in detail. S) Clauses on under-drainage arrangements and joints in lining have been elaborated. 6) Fig. 1 and 2 have been incorporated. For the purpose of deciding whether a particular requirement of this standard is complied with; the final value, observed or calculated, expressing the result of a test or analysis, shall be rounded oft' in accordance with IS 2: 1960 'Rules for rounding off numerical values (revI8~d)'. The number of significant places retained in the rounded off value should be the lame al that of thespecified value in this standard. IS 9451 : 1"4 Indian Standard GUIDELINES FOR LINING OF CANALS IN EXPANSIVE SOILS ( Second Revision) 1 SCOPE :1.1 This standard lays down guidelines ,lining of canals in expansive soils. for 4.1.2 Some of the soils which may be considered as cohesive non-swelling soils are all adequately compacted clayey soils, silty clays, sandy clays, gravelly sandy clays) etc, exhibiting cohesive properties and containing predominantly nonexpanding type clay minerals . and their combination with low plasticity with liquid limit not exceeding SO percent. NOTE - Black cotton soils are a type of expansive soil. 2 REFERENCES .2.1 The Indian Standards listed in Annex A are necessary adjuncts to this standard. 3 TERM INOLOGY .For the purpose of this standard the definition of terms given in IS 1498 : 1970 shall apply. 4 GENERAL 4.1 Expansive soils in side slopes and bed of canal in cutting or embankment when in contact with water swell, exerting a swelling pressure which may range from 50 to 300 kN/m 2 or more. This characteristic of swelling and the swelling pressures of black cotton soils is attributed to the pressure of montmorinolite or combination of montmorinolite and illite clay minerals. A wide range of properties of expansive soils are found in India ( see IS 1498: 1970 for identification and properties). The swelling pressure and free swell index tests should be done in accordance with IS 2720 ,( Part 40 ) : 1971 and IS 2720 ( Part 41 ) : 1977. Expansive soil met within the locality has to be analysed for swelling pressure before deciding the type of treatment. .For testing the expansive soil for determination of swelling pressure the expansive soil specimen should be remoulded at zero moisture content to the density obtainable at any time in the year in the field at a depth beyond 1·0 m (in expansive soil). The swelling pressure should be determined under no volume change condition when moisture content is increased from zero to full saturati on level. 4.2.3 eNS material should be non-swelling with a maximum swelling pressure of 10 kN/m 2 when tested in accordance with IS 2720 (Part 41 ) : 1977 at optimum moisture content and minimum cohesion (unconfined compression strength on saturated compacted soil, remoulded at OMC and compacted to standard proctor density) should be 10 kN/m l when tested according to IS 2720 ( Part 10) : 1991. 4.2.4 If given eNS material is not available, designed mix to produce blended eNS may be used. The artificial eNS should satisfy all the requirements of eNS. If stabilized material is to be used, special mix design needs to be evolved. 4.2.5 Most murums of laterite, laterite type and siliceous sandy clays exhibit eNS characteristics, however some murums may be of swelling type. Unlike swelling soils, they do not exhibit cracking during summer, nor heaving and stickiness during rainy season. Structures constructed on such soil do not exhibit heave though they may sometimes settle. The eNS are generally red, reddish yellow, brown, yellow, white, whitish grey, whitish yellow, green and greenish grey in colour. Although, several soils containing non-expanding type clay mineral exhibit eNS properties, the following range helps in locating such types: Percent Clay ( less than 2 microns) 15 to 20 Silt (0·06 mm-O·002 rom ) Sand ( 2 mm-O'06 mrn ) Gravel ( Greater than 2 mm ) Liquid limit Plasticity index 30 to 40 30 to 40 0 to 10 Greater than 30, but less than SO Greater than IS but less than 30 4.2 Cobesi,e Non-swelling Treatment SolIs (eNS) for ·4.2.1 They are soils possessing the property of cohesion of varying degree and non-expanding .type clay minerals such as illite and kaolinite 1 1SH511 JJJ4 S CRITERIA POR FIXING THE THICKNESS OFCNSLAYER 5.1 Thickness of eNS materials is related to swelling pressure and the resultant deformation, the permissible deformation being 2 em. 5.2 Guidelines for choosing the thickness of eNS materials required for balancing the different swelling pressures is given in Table 1. Slopes should be in accordance with IS 10430 : 1982. Table JA TblckDess or eNS Layer, CarrylDI Capacity Less Tban 2 Camees Discharle In Camec. ThlckDel1 , . . -_ _of eNS J.... Layer 10 em ( Min) __ Swell Pressure More Than ISO kN/m l Tbe construction should be carried out in tho foUowina'st.ps: a) While excavating prevision should be made for accommodating required thickness of eNS layer OD bed and sides. The subgradl on which eNS layer is to be laidshould generally not be kept exposed. for more than four days, prior to the placement of the eNS layer. b) Serrations should be provided in expan-· sive soil to prevent contact slides between eNS materials and expansive soil. c) Proper moisture should be added to eNS materials. d) eNS materials should be compacted in layers by appropriate equipment to ensure proper density. e) eNS on side slopes should be trimmed to the required thickness. The thickness is measured perpendicular to the surface of expansive soil. Swell Pressure SO·IS0 kN/m ' 1'4·2 0'7-1°4 60 50 75 60 0'3·0'7 0°03-0'3 40 30 SO 40 Table 18 Thickness Swelling Pressure of Soil Capacity of 2 Comecs and More or CNS Layer, Carrying Thickaess 01 eNS Materia Is f) Suitable canal lining over eNS materiat should be provided depending on the site and economy condition. g) To avoid slipping and rain cuts during the rainy season, it is advisable to provide eNS right up to the ground level. kN/nl l em ( Min) SO to 150 7S J50 to 300 8S 300 to SOO 100 NOTE - However, optimum thickness of eNS materials needs to be determined for different swelling pressures by actual experiments both in field and laboratory; if required. 6 CONSTRUCTION PROCEDURE To counteract the swelling pressure and prevent deformation of the rigid lining materials, a eNS material of required thickness depending on the swelling pressure of expansive soil, is sandwiched between the soil and the rigid lining material. The thickness of eNS layer should be measured perpendicular to the surface of expansive soil. 6.1 Canal in CuttlDI 6.1.1 Long deep cuts in expansive soils should be avoided and where possible a detour should be considered. In cutting special care will be necessary to compact the eNS materials against the excavated surface of the cuts. The material should be spread uniformly in their horizontal layers of specified thickness ( IS em thick). Care also is necessary in obtaining a good joint between the two materials. by thoroughly wetting tho excavated surface, 10 as to avoid slips at the junction plane. h) In deep cuts eNS material should be provided not only behind the lining of the canal but also above the canal prism, all along the excavated surface, so as to prevent large scale heaving above the canal level. The eNS material above the canal prism may be of lesser thickness, say IS to 20 em, However, full \ design thickness behind the lining should be continued at least 100 em above the top level of the lin ing (illustratory arrangement shown in Fig. 1 ). j) The stability of the slopes, particularly in . the case of cuts, is very adversely affected by rain water finding its way into the tension cracks and exerting hydrostatic force on the slipping mass of the soil. Covering the surface of the slopes byeNS materials and proper surface drainage will reduce the chances of rain water finding its way into the cracks. k) It is necessary to stack the excavated soil away from the cuts to prevent it inducing. slips by surcharge. 6.2 Canal In Embankment The construction should be carried out in the following steps: a) Proper moisture should be added to eNS · material and expansive solI. 2 C tUNING seC'nON IN FULL CUITING C C LINING SERVICE ROAD--! l eNS BLACK C01'TON SOIL eNS SECTION IN FULL EMBANKMENT FlO. b) Expansive soil and eNS material above ground level should be compacted simultaneously, in layers, with appropriate equipment to ensure proper density. c) The eNS materials in embankment should be laid and compacted in layers simultaneously with the body of the banks, so as to obtain good compaction and to avoid any slippage plane being developed between the two materials. The compaction of eNS materials should also be to the standard proctor density with optimum moisture content. It may be done either with sheep foot rollers or 8 to 10 ton ordinary rollers. d) Provision of surface drain and internal drainage filter should be made to minimize external/internal erosion. A rock toe with inverted filter may be provided at either end of canal bank. e) Special care is required to be taken to provide internal drainage for the banks, having bed filling of 2 metres or more. A sand blanket is spread on the base of the bank and rockfills with regular inverted filters are also necessary at the outer toes. f) For both the cuts and banks, paved surface drains should be provided at the berms, etc, to avoid erosion of the finished surface. As far as possible, water from these drains should be drained away from the canal. g) The drainage properties of the eNS material itself need to be given due consideration as water locked up in this saturated layer is likely to cause pore pressures on the lining during canal draw- j) To protect outer slopes from erosion, proper turfing should be used. 6.3 Similar procedure should be followed for canals in partial cutting and embankment. 6.4 Pride 6.4.1 The problem of effectively compacting the subgrade for side lining on slopes is very important in case of black cotton expansive soil zone in cutting or embankments, where backfill of eNS· material is required to be placed for the sides and bed, in addition to design thickness. Twenty em or so ( perpendicular to side slope) of extra pride may be provided and compacted in horizontal layers to the required density. This pride should be removed only just prior to the placement of lining, thus making a fresh and well compacted surface available for bedding. 6.4.2 For cutting in soft material where the eNS backfilling is not required the best method is to leave the cutting 20 em or so undercut ( perpendicular to the canal .slope ) and remove this undercut only just prior to the placement of concrete lining. Similar procedure may be adopted in case of cutting in hard strata. 6.5 Use of Polyethylene Sheets Below Concrete LiDlo, The use of polyethylene sheet below concrete lining could be either for achieving better ultimate imperviousness of the lining as a whole or it may be used only for limited purpose as an assistance, during construction, for avoiding the cement slurry from concrete escaping in the subgrade below. Use of LDPE sheets 200, gauge ( 50 micron) is to achieve only the latter' limited purpose. If overall imperviousness is down conditions. h) Murum ( gravelly soil) material on outer slopes of canal embankment should be trimmed to the required thickness. ' proposed to be achieved, it would be necessary to use HDPE-HM sheet of sufficient thickness. streDlth, toughness and durability. 3 'IS '451 : ItH 7 LINING 7.1 The concrete ( IS 3873 : 1993), burnt clay tile (IS 3872: 1966), stone pitched ( IS 4515: 1993), stone masonry (IS 11809: 1993) or lime concrete -( IS 7873 : 1975 ). may Such drainage holes are, however. not advocated for general adoption, lining be cement :8 UNDER DRAINAGE ARRANGEMENTS AND JOINTS IN LINING -8.1 The drainage properties of eNS material itself need to be given due consideration as water locked up in this saturated layer is likely to cause pore pressure on the lining during -canal draw down conditions. To release the, same if holes are provided for drainage in -concrete lining, care will have to be taken to provide inverted filters at the back of the holes -so as to avoid the eNS material being washed away by fluctuating water levels in the canal. 8.2 It is recommended to provide regular drainage arrangements using porous concrete sleepers, 7·7 em x 20 em with SO mm perforated 0.1. pipes at 3 m centre to centre comins out through the sides of the lining. Two porous concrete sleepers on either side of the bed. below the side may be provided. 'A 50 to 7S mm thick sand mat below the bed and side cast in-situ lining ( below the polyethylene sheet) should be provided. Where the sand mat is not economically feasible additional porous concrete sleepers may instead be provided at right angles to the longitudinal rails ( along the cross section of the canal) at 3 m centre to centre. The porous concrete sleepers have to be encased in filter material. An illustratory arrangement is shown in Fig. 2. G I PIPE CANAL BED c ,s. C C LINING C N SLAYER BOTTOM POROUS CONCRETE SLEEPER CAST IN SITU ON EITHER StOES OF CANAL BED G I PIPE RESTED ovsn'RAILS d THICKNESS OF CIS C C LINING d 1 THICKNESS OF eNS SOlc-BEtOW' OS LINING 1N EXPANSIVE SOl L FIG.2 ILLUSTRATORY DSTAIL OP BOTTOM RAILS ANNEX A ( Clause 2·1 ) IS No. 1498 : 1970 Title Classification and identification of soils for general engineering purposes (first revision) Methods of test for soils : Part 10 Determination of unconfined compressive strength ( reviled) Methods of test for soils: Part 40 Determination of free swell index of soils IS No. Title Methods of test foro soils: Part 41 Determination of swelling pressure of soils Code of practice for lining of canals with burnt clay tiles Laying cement concrete! stone slab lining on canals Code of practice 2720 ( Part 41 ) : 1977 2720 ( Part 10 ) : 1991 3872 : 1966 2720 3873 : 1993 ( Part 40 ) : 1977 4 IS 9451 : IH.t. IS Ni'. 4515 , 1993 Title Code of practice tor stone pitched linins for canals Code of practice for lime concrete lining for canals IS No. Tit/_ Code of practice for lining of canals by masonry Criteria for design of lined canals and guidelines forselection of type of lininl 11809 :1993 10430 : 1982 '873: 1975 5 Bareaaof ladl·· Sta.gra BIS is a statutory .institution established under' the Bur,au o/llIdla" Bfa_rill .Act', 19M to promote harmonious development' of the activities of stan~rdizatioD. markinl and quality certification of goods and attending to connected matters in the country. COPJrlaht DIS has a copyright of all its publications. No part of these publications may be reproduced in any form without the prior permission in writing of DIS. This does.not preclude, the free UIe, in the course of implementing the standard, of necessary details, such as symbols and sizes, type or grade designations. Enquiries relating to copyright be addressed to the Director ( Publications ). 81S. Review of Indian Standards AmeD~ents are !f.s~ed .to standards as the nee~ arises OD the b~sis of comments. Standards ~re also reviewed perIodIcally; a standard along wIth amendments IS reaffirmed when such a review indicates that no changes are needed; if the review indicates that cbanges are needed, it is tAkeD up for revision. Users of Indian Standards should ascertain that they are in possession of tho latest amendments or edition by referring to the latest issue of 'BIS Handbook' and 'Standards Monthly Addition'. This Indian Standard has been developed from Doc: No. RVD 13 ( 49 ) Am,admeDtl laaed Slnee PabUeatioD Amend No. Date of Issue Text Affected BURBAU OF INDIAN STANDARDS Headquarters: Manak BhavaD. 9 Bahadur Shah zafar Marl, New Delhi 110002 Telephones: 331 01 31, 331 13 75 Telegrams : Manaksanstha ( CoDimon to all Office. ) Regional Offices: Central: Manak Dbavan, 9 Bahadur Shah zafar Mars . NEW DELHI 110002 Eastern: 1/14 C.I.T. Scheme VII M. V.I.P. Road, Maniktola CALCUnA 700054 Northern: SeQ 445·446, Sector 3S-C, CHANDIOARH 160036 Telephone 331 01 31 { 331137S 37 84 99, 37 8S 61 { 37 86 26, 37,86 62 ::::::::::::::~8~:~:'~' ::~&::13 BOMBAY 430093 . . 53 38 43, 53 16 40 { S323'84 {:::.~;:: .:1.1: { 632 78 91, 632 78 92 . ~ . Branches: AHMADABAD. BAN~ALOkB.,;~tBIJOPAL~' BHUBA.N~HWAR.' COIMBATORB. . PAIUDABAD. GHA_~_. D~Opw,. AB, ' ,A~_'~H,.'.~, ...Q.MB.AD,,'_~ .~~AIPUR. KAN,\1L·. LUCKNOW. PATNA.1BIRUV~~~", ",:~; ,;,:> , ': " '. , ' "~ r" '" . ·...l,:f,;····,,·.;~:~~~~: ..~~i:~'?~·